I'm thinking of buying a ruger 10-22.  What would be a good scope to put on it?  I will only probably be shooting targets out to 100-150 yds.  I also dont want to spend $1000.  Maybe a small leupold rifleman?

Yes- nice
I have one that I believe is 2X7 . Midway sells it for $170, you might find it slightly cheeper elsewhere,I use
midway mostly because they give me a discount on my C&R FFL . Get the one piece weaver base which uses standard rings and toss the little narrow one that comes with the gun. This is less than $10 . The narrow one only  takes "rimfire" rings .  This scope is fairly compact and nice and clear ,great value. I find the low power setting to be of great use with its huge field of vision. If you go higher power you loose some of this and the scope starts to get longer and too big for this gun .
Put aside a couple of bucks to upgrade the trigger on this gun . The factory one is only fair but there are many deals out there to improve it which really makes this gun

this should be in the armory section 10/22 rimfire forum
i have a simmons 44mag on mine, target turrets, adjustable obj, nice and clear for only $100 at natchez

Remember that most rifle scopes have the parallax set at 100 yards...and a lot of 10/22 shooters will shoot at 50 yards from time to time...maybe even 25.  If you want to be able to do that, you'll need an AO scope that will go down to 25 yards.  Getting that in a Leupy will be a little pricy, but there are other scopes out the besides Leupold *GASP*...did I REALLY say that??

I have a Simmons Aetec 3.8x12 on one of mine, and a cheapass Bushnell Sportsman on the other.  Both have AOs that go down to 20 yards, and I do shoot them at 25, so that's worked out good.  I keep thinking to myself that I need to get a better scope than the Bushnell, but it works for the time being.  

If you look at rimfire scopes, the parralax is generally set to 50 yards...so don't rule out a "dedicated" rimfire scope if you don't want to mess with AO scopes.  

Just my .02, ymmv.  

I have a Weaver Classic Rimfire 2.5-7x28 scope on my .22.

It is fully multicoated (most rimfire scopes, including the Leupold, are not), and has surprisingly bright and clear glass.  It is made in Japan, not China.  I highly reccommend it.  They go for like $100 to $140.

-green

Bushnell 4-10x or 4-12x 40mm with adjustable objective.  I have used a couple of them for years with a rimfire.  You get parallax correction, variable power and decent optics for less than $100.  Zero is rock solid.  More power is good for squirrel head-shots!

I put a Leupold M8 4x28mm on mine.  Squirrels fear me.

I have a Simmons 4-12X40 AO. I like it.

+1 on the trigger upgrade especially if you like punching paper.

I am very glad I got the bull barrel.  It is suprising just how accurate it is at 50yds.

Good luck.

Seydou